Are Green Buildings in Fact Healthier?

The link between health and green building seems natural. More daylight, fresh air, and reduced emissions from fossil fuel read like a recipe for wellness. But there are those who use things like LEED certification as a marker of healthy building when the facts don’t always align with the claims.

For example, Duke Realty, an Indiana health-care-facility developer, extols on its website the healthy attributes of a recent project that achieved LEED Gold certification, asserting, “Green buildings typically have better indoor air quality than conventional facilities.” However, the certification was for LEED for Core & Shell. This category doesn’t include the finish-out of tenant spaces and avoids a primary culprit in indoor air quality: toxic emissions from finish materials.

On the other hand, a 2010 study done by Michigan State University titled “Effects of Green Buildings on Employee Health and Productivity” found that LEED buildings do create healthier work environments. Despite the fact that the scope of the research was limited to only two case studies (the Christman Building and the Michigan State University Federal Credit Union), the authors of the report concluded that “these preliminary studies lend support to expectations of improved IEQ [indoor environmental quality] and occupational health and public health outcomes from expanded use of green office buildings.” Expectations are not evidence, and the Michigan State researchers were aware of the limitations of drawing conclusions from subjective employee surveys, their method of evaluation in this study.

Common sense and a lot of science warn that breathing toxic chemical gases in unventilated or unexhausted environments is hazardous. That’s the presumptive logic on which this and similar studies are based. Future research will most likely broaden its scope to measure accurately the cause before extrapolating its effect.

Fact fishing and sound bites

This is why studies, particularly those of the preliminary kind, are so susceptible to distortion. A 2011 Fox News headline shouted out: “Green Buildings, Hazardous to Health?” Beyond that hyperbole, the story cherry-picked its way through an Institute of Medicine study on the potential impacts of climate change on IEQ. The story focused on the possible negative effects of “weatherization” methods such as adding insulation and tighter construction.

“To say something is green because you’ve increased tightness or insulation is inappropriate,” says Carnegie Mellon architecture professor Vivian Loftness, a coauthor of the study. She points to the passive-house technique of using heat-exchange ventilation as an example of green building that actually improves fresh-air delivery rates compared with conventional homes. “It’s a package deal; you don’t build supertight without a ventilation system,” she adds.

The Fox story also omitted the recommendations of the researchers, which called for updated codes, more testing, and regulation by the EPA of toxic emissions from materials.

Some researchers have criticized the U.S. Green Building Council (USGBC) for the fact that it’s possible to tailor a LEED Platinum certification without any indoor-air-quality credits. But the critics provide no data to show how LEED buildings actually perform.

The National Research Council of Canada released a study this year that is the most extensive to date on how green buildings perform in terms of indoor air quality. Comparing 12 pairs of conventional and green buildings (most were LEED-certified or candidates), the study found that the green buildings did have better indoor air quality. According to research-team member Guy Newsham, the data supported the premise that such buildings have lower levels of indoor pollutants and higher ratings for occupant well-being, among other positive attributes.

Data wars and the vinyl conundrum

By most measures, vinyl is an incredible material—it’s strong, durable, cheap, and infinitely moldable. But no other industry has struggled longer for green credentials than vinyl manufacturers.

The Vinyl Institute’s website touts the material as safe and plays up its green virtues. It highlights recycling programs, material efficiency, and low energy use in manufacturing. Then why do the USGBC and the Living Building Challenge have various precautions about the use of vinyl? The problem with vinyl, or polyvinyl chloride (PVC), is that it raises serious health questions at every phase of its life cycle.

“Chlorinated compounds [like PVC] don’t have a good track record in human health and the environment,” says Robin Guenther, a principal and Sustainable Healthcare Design Leader at Perkins +Will. She adds that vinyl manufacturing creates dioxins, highly toxic substances that can be released if the vinyl is burned or during disposal. Its production also yields vinyl chloride monomer (VCM), a known human carcinogen, and EDC, a suspected carcinogen.

In terms of reducing hazards at the end of life, the Vinyl Institute spotlights the recycling angle, but less than half of 1 percent of PVC is currently recycled, according to data from the EPA.

The Living Building Challenge’s materials Red List prohibits the use of PVC, but LEED has taken a more tentative path. Currently, LEED offers a pilot credit for avoiding the phthalates in vinyl products and other “chemicals of concern.” Phthalates, used to soften otherwise brittle material, have been linked to hormone disruption in male infants in an often-cited University of Rochester study.

According to Guenther, the vinyl industry and the American Chemical Council (ACC) reacted to the LEED credit by launching an aggressive public-relations offensive against the USGBC and by lobbying Congress to prevent the government from mandating LEED on federal projects. The ACC promotes substituting the industry-created Green Globes system, which has no credits for avoiding materials that contain chemicals of concern to human health.

Shedding daylight on learning

The benefits of daylighting have proved difficult to quantify and often lead to exaggerated claims and conflicting reports. In the 1970s, one daylighting study showed that students learned equally well whether classrooms had windows or not. Anxious to save Btus during the energy crisis, school boards and designers often reduced fenestration in new schools based on limited research.

In 1999, a Heschong Mahone Group paper showed a link between daylight and improved test scores. The authors were clear that the findings didn’t specifically show that students learn more in the presence of daylight—but they indicated an “association,” or simultaneous occurrence of daylight and higher scores. Many in the building sector jumped on the data in a skewed and overly simplified form.

“I can’t tell you how many PowerPoint presentations I’ve seen that say, ‘Daylighting makes kids 25 percent smarter,’ ” says Lindsay Baker, coauthor of a USGBC report that summarizes research pertaining to sustainable design and schools. Baker notes that the Heschong Mahone study wasn’t intended as a design guide. She asserts that while preliminary studies laid a foundation, research now needs to pinpoint how a particular cause in the environment affects a specific area in our bodies. She cites a study this year by the Lighting Research Center at the Rensselaer Polytechnic Institute demonstrating that when students were deprived of the shortwave radiation present in daylight, they lost the ability to regulate the hormone melatonin, leading to disrupted sleep patterns and reduced alertness.

Accessing the data

Navigating through this messy gumbo of information presents a challenge for practitioners who need to make design decisions that affect occupant health.

Chris Pyke, vice president of research at the USGBC, points to the lack of a good interface between solid research and the design practitioners who need to implement that research in the built environment. According to Pyke, LEED can play a limited role by incorporating current research into the development and application of new credits. Part of the answer could be in “evidence-based design,” an innovative approach currently used in health-care facilities. The Center for Health Design certifies architects and other building professionals to use a comprehensive system for making informed decisions based on finding, interpreting, and implementing solid research.

“It would be really exciting if we can expand the concept of evidence-based design to other domains, like schools, which are ripe for this kind of transformation,” says public-health researcher Matthew Trowbridge. He is part of an energetic movement in the green-building community to look at occupant health through different disciplinary lenses. “Obviously, minimizing toxic exposures is important, but how do you use the design of buildings to promote health through encouraging healthy behaviors, social well-being, and productivity?” says Trowbridge.

As we refine our approach to health issues, the goal, in the words of Lindsay Baker, is to make buildings that not only don’t make us ill, but help us to thrive.